Preheat oven to 350°F. Grease the bottom of a 9x13-inch baking dish with cooking spray.

In a medium bowl, whisk together the egg, mayonnaise, parsley, lemon zest, and Old Bay. Add the crab meat, bell pepper, green onions and crushed crackers; fold to combine.

Lay the flounder fillets on a clean work surface (nicest looking side facing down). Divide the crab mixture between the fillets. Starting at the tail end, roll up each fillet and place in the prepared baking dish, seam side down. Brush or drizzle with melted butter, then season the tops with additional Old Bay. Bake for 25-30 min.

While the fish bakes, make the sauce. In a small saucepan, combine chicken broth, lemon juice and shallot. Bring it to a boil over medium-high, then reduce to medium and simmer for about 7 minutes. Stir in the capers, then take it off the burner. Whisk in the chilled butter, once piece at a time, until the sauce has thickened. Stir in the parsley. Taste and season with kosher salt and black pepper to taste.

Spoon the sauce over the stuffed flounder and serve.

Recipe courtesy of Sip & Sanity
https://www.sipandsanity.com/crab-stuffed-flounder...